Ni掺杂AlN铁磁性的第一性原理研究

FIRST-PRINCIPLE STUDY FOR FERROMAGNETISM OF Ni-DOPED AlN

采用密度泛函理论(DFT)的总体能量的平面波超软赝势方法,结合广义梯度近似(GGA),对Ni掺杂AlN32原子超原胞体系分别进行了几何结构优化,计算和分析了Ni掺杂AlN的结构、能带、电子态密度、集居数及体系总能.结果表明,Ni掺杂AlN会产生自旋极化,能带结构显示6.25%Ni掺杂AlN呈现半金属性质,有铁磁性,铁磁性可以用Ni和相邻的N之间的p-d杂化机制来解释.Ni掺杂的AlN应该是一种有应用前景的稀磁半导体DMS.

The geometrical structure of Ni doped 32-atom supercell of AlN was investigated using the ultra-soft pseudopotential method of total-energy plane wave based on the density functional theory（DFT）.Band structures,partial density of states,mulliken charges,electron density differences and total-energy of Ni doped AlN crystals were calculated and analyzed in details.The results revealed that the Ni dopants were found spin polarized.Band structures show a half metallic behaviour.The ferromagnetic ground state in Ni-doped AlN can be explained in terms of p-d hybridization mechanism.These results suggest that Ni-doped AlN presents a promising dilute magnetic semi-conductor.